Screw holding anchor



I c. N. ACKERMAN. I SCREW HOLDING ANCHOR. APPLICATION FILED JAN-15. I921.

Patented May 16, 1922.

(PM scr w El A a CHAR-LES N, ACKERMAN, OF CHICAGO, ILLINCIS, AErFdIGrN'0B, TO ACKERMAN- JOHNSON CO., A CORPORATION OF ILLINOIS.

SCREW HOLDING ANCHOR.

Specification of Letters Patent.

Application filed January 15, 1921; Serial No. 437,493.

To all 107mm it may cow meme:

Be it known that 1, CHARLES N. Aonnn- MAN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Screw Holding Anchors, of which the following is a specification.

This invention relates to improvements 111 screw holding anchors.

One of the objects of the invention is to provide an improved screw holding anchor adapted especially for inclusion in plastic moldable bodies.

Another object is to provide an improved screw holding anchor and a method and means for applying it.

Another object is to provide an anchor of low cost, great strength. and so placed in a molded body that the stress thereon will. not *ause the material surrounding its smaller end to crack or shale ofl.

Other, further and more specific objects of the invention will become readily apparent, to persons skilled in the art, from a considcration of the following description when t: ,n in conjunction with the drawings, via rein 1 shows a central vertical section through the anchor and variations, and the method and means of mounting it, on the form or wall for supporting or confining moldable material.

Fig. 2 shows the device in place within a body of moldable material.

Fig. 3 an elevation of the screw holding anchor, or shell.

in all the views the same reference characters are employed to indicate similar parts.

The device is especially intended for incor poration in walls, floors, ceilings, or similar structures made of plastic, inoldable material, such as cement plaster, concrete, or the like.

In forming structures of conglomerate plastic material, supports or forms are usually provided for confining the moldable material to be used, until it sets or becomes hardened, after which the supports are removed.

My anchor is to be embedded in such structures and used in association with suitable screws or bolts to mechanically attach and hold any object that may be fastened thereto by use of screws, bolts, or the like.

The anchor consists of'a hollow conoidal shell, having a wall preferably of uniform thickness, the sides of the smaller end being, preferably, approximately parallel, the larger end outwardly diverging or flaring at a greater angle from near the mid portion to leave clearance space for the inner end of the screw and provide a conical wedging structure in rear of the front end to receive and withstand the stress that may be exerted by the screw that is subsequently to be inserted in the anchor. I

' The shell 5 may be made of a casting, or from a sheet of suitable metal. It is internally screw threaded as at 6 to engage and hold a screw that subsequently may be inserted therein.

A. cap 7, formed of relatively thin sheet metal, is secured to the larger end 8 of the anchor to close the opening 9, to prevent the entrance of cement or moldable material therein. The sidewalls, on opposite sides, are provided with laterally extending wings ll) to prevent rotation of the anchor when the screw applied thereto. T beside wings 10, in the particular device shown, consist of portions of the metal extending radially from the body, shown in Figs. 2 and 3.

His a wall of the form, for supporting or confining a body of plastic material 12 which is to be placed thereon.

At intervals, where the anchors 5 are to be inserted in the wall 12, a relatively short screw 13 having a tapered or conoidal head A, is placed upon the support 11 and secured in selected localities by the insertion of a pin. nail, or the like, 15, through the central bore made through the screw 13. When the screws 13 are thus located, the anchors 5 are screwed upon the threaded stems of the screws until their lower ends are brought into substantial contact with the tapered or conoidal head 13 of the screw. This spaces the anchors away from the upper surface of theforin 11 and provides a chamfered or tapered orifice 16 in the surface of the wall 12 when the screw 13 is removed, providing a guide for the screw to be subsequently inserted. A screw 1-" without the head 14: may be used, or a screw 13 may be passed through the wall 11 in which event the pin 15 will not be required. After the plaster has hardened the screws 13 must be removed to take away the wall 11 after which the same or similar screws may be used to attach objects to the wall or body 12.

After the anchors 5 have been mounted upon the supports 13 in selected localities, upon form or support 1]., which are fixed in position by means of the pin or nail 15 that passes through the threaded member 13, the concrete or nioldable material is poured upon the support 1d until it surrounds the anchor, or a substantial part thereof, as more clearly shown in Fig. 2. After the concrete 12 has set orbecome hardened the wall support or form 11 is removed and disengaged from the pins or nails '15, leaving the pins in the position shown in Fig. 1 within the anchor members 5 and the support 18 -13. Now, after the forms have been removed the screws 13-13 areremoved from the anchor 5 and the pins or nails 15 are taken out of the anchors with the screws and thereupon the anchors are ready for the use for which they are intended.

When a screw is inserted in the embedded anchor and strain-is impressed thereon tending to move the anchor axially of its posi tion, the greatest lateral stress effected thereby isproduced at the rear or upper end of the anchor because at that point the greatest flaring or tapering of the wall of the anchor is present, and the lower portion of the wall 12 is not stressed to the same extent.

The chamfered hole 16 serves as a guide for the screw and provides a larger body of material between the lower surface of the wall and the lower end of the screw, locating theanchor further into the body of the wall thanwould be if the lower end of the anchor rested directly upon the form 11 as shown by use of screws 13 and 13.

-The screws 13 and the pins 15 may be used indefinitely as they serve only as means for supporting and holding the anchors temporarily in desired localities.

While I have herein shown a single embodiment of my invention for the purpose of clear disclosure, it will be manifest, to persons skilled in the art, that there may be variations in the general arrangement and configuration'of the parts within the scope of the appended claims.

Having described my invention what I claim as new and desire to secure by Letters Patent, is

1. A screw holding anchor adapted to be embedded in moldable material, comprising a wall insert having a substantially cylindrical shaped internally threaded lower portion and an inverted bell shaped hollow upper portion, an externally projecting lug on the insert, a cap completely closing off the said upper portion of the insert, a conoidal headed supporting member having a bod portion threading into the said cylindrical internally threaded lower portion of the insert, and means for holding the device in position while moldable material is being poured and permitted to harden.

2. A screw holding anchor, adapted to be embedded in moldable material, comprising a wall insert having a lower internally threaded portion of substantially uniform diameter and an upper outwardly flaring unthreaded portion, an externally projecting lug on the insert, a substantially semi-spherically shaped cap having an annular flange telescoped over the flaring upper portion of the insert, and a supporting member comprising a body portion threaded into the lower portion of said insert and adapted to be removed from the insert after the moldable material has hardened.

In testimony whereof I hereunto subscribe my name.

CHARLES N. ACKERMAN. 

